Some rough math… a cord of green maple/ash/birch contains 320 gallons of water. 6x = 1,920 gal.
About 3/4 of that would have air-dried away, which is about 1,440 unnecessary gallons.
It takes roughly 10,000 BTUs to boil off a gallon of ice water, so total of 14.4 million BTUs. When dry, each cord contains 20 million.
So, you burned 3/4 of a cord extra just getting rid of that water. Probably that much again just from inefficient combustion. So I’m going to guess 4-5 cords in ideal conditions.